Head stack assembly cartridge

ABSTRACT

According to one aspect of the present disclosure, a head stack assembly cartridge is provided. The head stack assembly cartridge includes a base plate having a pivot shaft for pivotally mounting a head stack assembly and a base voice coil motor magnet attached to an inner surface of the base plate. The base voice coil motor magnet is arranged on the inner surface of the base plate to be adjacent to a coil of the head stack assembly pivotally mounted on the pivot shaft. The head stack assembly cartridge further includes a cover removably attached to the base plate and a pivot clamp removably attached to the cover and configured to secure the head stack assembly pivotally mounted on the pivot shaft.

FIELD

The present disclosure generally concerns a hard drive component testingplatform and, in particular, is directed to a head stack assemblycartridge.

BACKGROUND

Component testing plays an important role during the manufacture andassembly of hard drives. Testing individual components allows themanufacturer to determine whether specifications of a new design havebeen met prior to incorporating the new component into a fully assembledhard drive. Testing representative component samples provides a measureof quality control that may prevent the wasteful assembly of a largenumber of hard drives using a faulty batch of components. However, manyconventional hard drive component testing systems fail to create atesting environment similar to that experienced by components in anoperating hard drive. Accordingly, these conventional systems arelimited in the number and range of parameters that can be tested beforethe component is incorporated into a working hard drive.

Conventional testing systems typically are expensive and relativelycomplex systems. Conventional testing systems may cost several hundredsof thousands, and possibly millions, of dollars to purchase andmaintain. This expense limits the number of testing systems amanufacturer can purchase given a limited budget, which correspondinglylimits the number of components that can be tested within a given timeframe. Many conventional component testing systems are complex pieces ofequipment requiring special training and/or special tools to set up andoperate. This complexity limits the efficiency and increases the overallcosts associated with operating and maintaining the systems.

SUMMARY

The head stack assembly cartridge described in the present disclosure ispart of a modular hard drive component tester designed to address theforegoing deficiencies of conventional testing systems. This novel harddrive component tester is designed to use as many production hard drivecomponents as possible to both keep down costs of the testing platformand to help recreate a testing environment similar to that experiencedby components in an operating hard drive. As described herein, variousstructures from production hard drives have been modified to provide areliable and relatively easy to operate tester.

According to one aspect of the present disclosure, a head stack assemblycartridge is provided. The head stack assembly cartridge includes a baseplate having a pivot shaft for pivotally mounting a head stack assemblyand a base voice coil motor magnet attached to an inner surface of thebase plate. The base voice coil motor magnet is arranged on the innersurface of the base plate to be adjacent to a coil of the head stackassembly pivotally mounted on the pivot shaft. The head stack assemblycartridge further includes a cover removably attached to the base plateand a pivot clamp removably attached to the cover and configured tosecure the head stack assembly pivotally mounted on the pivot shaft.

According to another aspect of the present disclosure, a method for testmounting a head stack assembly is provided. The method includespivotally mounting a head stack assembly on a pivot shaft of a baseplate. A cover plate is attached to the base plate, wherein the coverand the base plate partially enclose the head stack assembly. Thepivotally mounted head stack assembly is secured with a pivot clampattached to the cover plate.

It is understood that other configurations of the subject technologywill become readily apparent to those skilled in the art from thefollowing detailed description, wherein various configurations of thesubject technology are shown and described by way of illustration. Aswill be realized, the subject technology is capable of other anddifferent configurations and its several details are capable ofmodification in various other respects, all without departing from thescope of the subject technology. Accordingly, the drawings and detaileddescription are to be regarded as illustrative in nature and not asrestrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a hard drive component test platformaccording to one configuration.

FIG. 2 is a perspective view of a test platform chassis according to oneconfiguration.

FIG. 3 is an exploded view of a disk spindle assembly pack according toone configuration.

FIG. 4 is an exploded view of a head stack assembly cartridge accordingto one configuration.

FIG. 5 is a perspective view of a head stack assembly cartridgepivotally coupled to a disk spindle assembly pack according to oneconfiguration.

FIG. 6 is a perspective view of a hard drive component test platformaccording to one configuration.

FIG. 7 is a flowchart depicting steps of a method for test mounting ahead stack assembly according to one configuration.

DETAILED DESCRIPTION

The detailed description set forth below is intended as a description ofvarious configurations of the subject technology and is not intended torepresent the only configurations in which the subject technology may bepracticed. The appended drawings are incorporated herein and constitutea part of the detailed description. The detailed description includesspecific details for the purpose of providing a thorough understandingof the subject technology. However, it will be apparent to those skilledin the art that the subject technology may be practiced without thesespecific details. In some instances, well-known structures andcomponents have been simplified or omitted from the figures to avoidobscuring the concepts of the subject technology.

FIG. 1 is a perspective view of hard drive component tester 10 accordingto one embodiment. Tester 10 provides a modular testing platformcomprising four primary components: tester chassis 20, disk spindleassembly cartridge 40, head stack assembly cartridge 60, and printedcircuit board assembly 80. Tester chassis 20 is configured to allow eachof the other components to be mounted and dismounted from tester chassis20 by an operator. Disk spindle assembly cartridge 40 contains amagnetic disk mounted to a spindle motor configured to rotate the disk.Head stack assembly cartridge 60 contains a head stack assembly and isconfigured to be mated with disk spindle assembly cartridge 40. Printedcircuit board assembly 80 contains firmware and power and controlcircuitry used to operate the spindle motor in disk spindle assemblycartridge 40 and the head stack assembly in head stack assemblycartridge 60 as well as to interface with a tester controller such as acomputer configured to run tests using tester 10 and record the results.

FIG. 2 is a perspective view of tester chassis 20 according to oneembodiment. Tester chassis 20 includes chassis plate 21, base plate 22,a plurality of pillars 23, a plurality of clamps 24, and a printedcircuit board assembly mount 25. In the exemplary configuration shown inFIG. 2, two clamps 24 are attached to an upper surface of chassis plate21 and arranged to allow an operator to removably mount disk spindleassembly cartridge 40 and head stack assembly cartridge 60 to the uppersurface of chassis plate 21. Clamps 24 may be toggle clamps or otherclamping devices known to those skilled in the art. In addition toclamps 24, tooling ball 26 and cartridge support 27 are also attached tothe upper surface of chassis plate 21. Tooling ball 26 provides a stopto help align disk spindle assembly cartridge 40 when being mounted onthe upper surface of chassis plate 21. Cartridge support 27 supportshead stack assembly cartridge 60 when mated to disk spindle assemblycartridge 40 and mounted on tester chassis 20. In certainconfigurations, screws or other fasteners may be used to mount andsecure disk spindle assembly cartridge 40 and/or head stack assemblycartridge 60 to the upper surface of chassis plate 21.

Printed circuit board assembly mount 25 provides a platform for mountingprinted circuit board assembly 80 to tester chassis 20. Printed circuitboard assembly 80 may be mounted to an upper surface of mount 25 usingscrews or other fasteners. Mount 25 may be made from a metal or metalalloy, such as aluminum, and insulative supports or spacers may bepositioned between mount 25 and printed circuit board assembly 80. Mount25 may be attached to chassis plate 21 using slide assemblies 28, whichallow mount 25 to be raised and lowered with respect to chassis plate21. Mount 25 may be held in a raised position with respect to chassisplate 21 using one or more clamps 29 attached to the bottom surface ofchassis plate 21. Using this configuration, printed circuit boardassembly 80 mounted to mount 25 can be lowered away from chassis plate21 when mounting head stack assembly cartridge 60 and/or disk spindleassembly cartridge 40. After head stack assembly cartridge 60 and/ordisk spindle assembly cartridge 40 are secured to the upper surface ofchassis plate 21, mount 25 can be raised using clamp 29 to bring printedcircuit board assembly 80 into electrical contact with head stackassembly cartridge 60 and disk spindle assembly cartridge 40. In thisregard, printed circuit board assembly 80 includes a first interfaceconfigured to make electrical contact and communicate electrical powerand signals with the spindle motor in disk spindle assembly cartridge40. Printed circuit board assembly 80 also includes a second interfaceconfigured to make electrical contact and communicate electrical powerand signals with a flex cable assembly of the head stack assemblymounted in head stack assembly cartridge 60. Printed circuit boardassembly 80 further includes a third interface configured to makeelectrical contact and communicate electrical signals with a testercontroller.

Printed circuit board assembly 80 may be similar or identical to printedcircuit board assemblies used in hard drives using similar or identicalinterfaces for communicating with connected components. Using productionprinted circuit board assemblies reduces costs involved in implementingtester 10 and allows for standard interface connections and protocols tobe used for communication between tester 10 and the tester controller.Furthermore, production flex cable assemblies and spindle motors may beconnected to printed circuit board assembly 80 with little or nomodification to the interfaces used to connect these components inproduction hard drives.

In the exemplary configuration shown in FIG. 2, chassis plate 21 issupported by a plurality of pillars 23, which are mounted to base plate22. Pillars 23 secure chassis plate 21 above base plate 22 withsufficient height to allow the operation of clamp 29 to raise and lowerprinted circuit board assembly mount 25. In alternative configurations,chassis plate 21 may be mounted in a rack or other support structureinstead of pillars 23 and base plate 22. Chassis plate 21, base plate 22and pillars 23 may be made from a metal or metal alloy, such asaluminum, and may be attached to one another using screws, welding,adhesives, or other known fasteners.

FIG. 3 is an exploded view of disk spindle assembly cartridge 40according to one embodiment. Disk spindle assembly cartridge 40 includesbase 41, spindle motor 42, magnetic disk 43, disk clamp 44, and coverplate 45. Spindle motor 42 is attached to an inner surface of base 41and is configured to make electrical contact with an interface onprinted circuit board assembly 80 when mounted on tester chassis 20.Spindle motor 42 may be similar or identical to spindle motors used inproduction hard drives. Spindle motor 42 may be attached to the innersurface of base 41 using screws or other fasteners known to thoseskilled in the art.

Magnetic disk 43 is seated on spindle motor 42 and secured to spindlemotor 42 by disk clamp 44. Disk clamp 44 may be attached to spindlemotor 42 using screws or other fasteners through a central opening inmagnetic disk 43. As the screws or other fasteners are tightened, theperimeter of disk clamp 44 applies pressure on the upper surface ofmagnetic disk 43 thereby preventing slippage between magnetic disk 43and a spindle of spindle motor 42. Magnetic disk 43 and disk clamp 44may be similar or identical to magnetic disks and disk clamps used inproduction hard drives.

Magnetic disk 43 may be encoded with servo data used as initial seeds togenerate servo tracks on magnetic disk 43 for positioning a head gimbalassembly at an intended position to conduct tests. Magnetic disk 43 alsomay be encoded with servo tracks ready for use in positioning a headgimbal assembly at an intended position to conduct tests. In addition,application information supplementing servo patterns on magnetic disk 43may be encoded on magnetic disk 43 or at another storage locationaccessible to a test controller executing tests using tester 10. Theapplication information supplementing servo patterns may includeinformation on any deviation of each track with respect to roundness andspacing of adjacent tracks on magnetic disk 43, defects on the surfaceof magnetic disk 43, etc. Information for performing channeloptimization for purposes of testing also may be encoded on magneticdisk 43.

Cover plate 45 is attached to base 41, which together partially enclosemagnetic disk 43. Cover plate 45 may be attached to base 41 using screwsor other fasteners. An opening is defined along one side of disk spindleassembly cartridge 40 that provides access to magnetic disk 43 by a headstack assembly when disk spindle assembly cartridge 40 is mated withhead stack assembly cartridge 60. As will be discussed in more detailbelow, disk spindle assembly cartridge 40 may be mated with head stackassembly cartridge 60 using pivot pin 47 set in base 41 and alignmentmount 48 of base 41. In one configuration, cover plate 45 defines anopening in which transparent window 46 is set to allow visualobservation during operation of test station 10. Window 46 may be madeof plastic or glass. Window 46 may be set in the opening of cover plate45 using an adhesive or may rely on a pressure fit to remain set. Base41 and cover plate 45 may be made of a metal or metal alloy fordurability and strength. For example, base 41 and/or plate 45 may bemade from aluminum or an aluminum alloy. Alternatively, a more durablematerial such as stainless steel may be used for base 41 and/or plate45.

FIG. 4 is an exploded view of head stack assembly cartridge 60 accordingto one embodiment. Head stack assembly cartridge 60 includes base plate61, pivot shaft 62, base magnet 63, head stack assembly 64, cover plate65 and pivot clamp 66. As shown in FIG. 4, pivot shaft 62 and basemagnet 63 are arranged on an inner surface of base plate 61. Pivot shaft62 is arranged on the inner surface of base plate 61 to pivotally mounthead stack assembly 64. Specifically, pivot shaft 62 is arranged toengage a pivot assembly of head stack assembly 64, which allows anactuator coil assembly of head stack assembly 64 to pivot about pivotshaft 62. Base magnet 63 is positioned on the inner surface of baseplate 61 to be adjacent to a coil of head stack assembly 64 when mountedto form a voice coil motor for controlling the movement of the actuatorcoil assembly about pivot shaft 62. Stops 67 and 68 are arranged on theinner surface of base plate 61 to limit the range of rotation (i.e.,angular displacement) in either direction of rotation available to theactuator coil assembly of head stack assembly 64. Ramp 69 is arranged onthe inner surface of base plate 61 for parking the actuator coilassembly when not in operation. Stops 67 and 68 and ramp 69 may besimilar or identical to those used in production hard drives.

As noted above, head stack assembly 64 includes an actuator coilassembly having a pivot assembly and a coil. Head stack assembly 64further includes a flex cable assembly for electrically connecting headstack assembly 64 to an interface on printed circuit board assembly 80.Electrical power and control signals are communicated between printedcircuit board assembly 80 and head stack assembly 64 via the flex cableassembly. Head stack assembly 64 may be similar or identical to headstack assemblies used in production hard drives. For example, testingplatform 10 may be used to test the head stack assembly prior to beingassembled in a production hard drive. Alternatively, head stack assembly64 may be modified to allow head gimbal assemblies to be detachablymounted for testing. For example, the actuator coil assembly may bemodified to include the mounting mechanism described in U.S. patentapplication Ser. No. 12/500,546, entitled “Head Gimbal Assembly MountingMechanism” and filed on Jul. 9, 2009, and the clamping mechanismdescribed in U.S. patent application Ser. No. 12/494,869, entitledDual-State Clamping Mechanism” and filed on Jun. 30, 2009, both of whichare hereby incorporated by reference herein.

Cover plate 65 is attached to base plate 61 using screws or otherfasteners that allow cover plate 65 to be removable from base plate 61.In one configuration, cover magnet 70 is attached to the inner surfaceof cover plate 65. Cover magnet 70 is arranged on the inner surface ofcover plate 65 to be adjacent to the coil of head stack assembly 64 whenmounted on pivot shaft 62 and opposite base magnet 63. Base magnet 63,cover magnet 70 and the coil of head stack assembly 64 form a voice coilmotor for controlling the movement of the actuator coil assembly of headstack assembly 64.

Head stack assembly 64 may be attached to pivot shaft 62 using pivotscrew 71. To secure and stabilize head stack assembly 64 duringoperation, pivot clamp 66 is attached to cover plate 65 with load screw73 to apply a load to pivot screw 71 attaching head stack assembly 64 topivot shaft 62. In the exemplary configuration depicted in FIG. 4, pivotclamp 66 is a triangular plate with two corners configured to be seatedon pins 74 and 75 set in cover plate 65. Pin 76 is set in the thirdcorner of pivot clamp 66 and is arranged to be seated on the head ofpivot screw 71. Load screw 73 may be arranged along the altitude of thetriangular plate extending from the third corner to the mid-pointbetween the other two corners in order to balance pivot clamp 66 betweenpins 74 and 75. Tightening load screw 73 increases the load placed onthe head of pivot screw 71 with pins 74 and 75 acting as a fulcrum forpivot clamp 66, which stabilizes the actuator coil assembly of headstack assembly 64 during operation of tester 10. In an alternativeconfiguration, pivot clamp 66 may be attached to cover plate 65 with ahinge and preloaded with a spring to apply a load to pivot screw 71.Load screw 73 may be used to increase the load applied to pivot screw 71above what is available using the spring alone.

In an alternative configuration, cover plate 65 may be attached to baseplate 61 with a hinge along one side of cover plate 65 and acorresponding side of base plate 61. A clamp screw or other fastener maybe used on the opposite side of cover plate 65 and base plate 61 to holdthe two components together. This hinged implementation of cover plate65 and base plate 61 allows relatively easy access inside head stackassembly cartridge 60 to facilitate the exchange of head stack assembly64 and/or a head gimbal assembly detachably mounted on the actuator armof head stack assembly 64.

Base plate 61, cover plate 65 and pivot clamp 66 may be made of a metalor metal alloy for durability and strength. For example, aluminum or analuminum alloy may be used for base plate 61, cover plate 65 and/orpivot clamp 66. Alternatively, a more durable material such as stainlesssteel may be used for base plate 61, cover plate 65 and/or pivot clamp66.

Base plate 61 further includes pivot arm 77 and alignment mount 78.Pivot arm 77 defines a bore which is arranged to receive pivot pin 47 ofdisk spindle assembly cartridge 40 to pivotally couple head stackassembly cartridge 60 with disk spindle assembly cartridge 40. FIG. 5 isa perspective view of head stack assembly cartridge 60 pivotally coupledto disk spindle assembly cartridge 40 according to one embodiment. Ashead stack assembly cartridge 60 is pivoted with respect to disk spindleassembly cartridge 40, alignment mount 78 on head stack assemblycartridge 60 ultimately meets and aligns with alignment mount 48 on diskspindle assembly cartridge 40 in a closed position. Specifically,alignment mounts 48 and 78 may be configured with opposing steps so thatalignment mounts 48 and 78 interlock with both vertical and opposingmating surfaces. In this manner, head stack assembly cartridge 60 isaligned with disk spindle assembly cartridge 40 to allow head stackassembly 64 to access magnetic disk 43 contained within disk spindleassembly cartridge 40. Thumb screw 79, or another fastener, may be usedto lock alignment mounts 48 and 78 together.

When mated together, disk spindle assembly cartridge 40 and head stackassembly cartridge 60 create an internal environment similar to that ofa production hard drive. The interior dimensions of disk spindleassembly cartridge 40 and head stack assembly cartridge 60 are similarto those of a production hard drive. This similarity both allowscomponents from production hard drives to be used in these modules aswell as creates similar environmental conditions under which componenttesting can be performed.

The configurations of the disk spindle assembly cartridge and the headstack assembly cartridge are not limited to those described above. Forexample, the disk spindle assembly cartridge may include more than onemagnetic disk seated on and secured to the spindle motor.Correspondingly, the head stack assembly in the head stack assemblycartridge may include multiple head gimbal assemblies arranged to accessone or both sides of each of the magnetic disks in the disk spindleassembly cartridge.

FIG. 7 is a flowchart depicting steps of a method for test mounting ahead stack assembly according to one configuration of the componentsdescribed above. In step S701, head stack assembly 64 is pivotallymounted on pivot shaft 62 of base plate 61. As discussed above, pivotshaft 62 may engage a pivot assembly of head stack assembly 64 and beattached to head stack assembly 64 with pivot screw 71. In step S702,cover plate 65 is attached to base plate 61 using screws or otherfasteners. As described above, base plate 61 and cover plate 65partially enclose head stack assembly 64. In step S703, pivotallymounted head stack assembly 64 is secured with pivot clamp 66 attachedto cover plate 65. In this manner, head stack assembly 64 is stabilizedduring operation. Pivot clamp 66 may be attached to cover plate 65 usingload screw 73, which is operable to apply a load to pivot screw 71 bytightening load screw 73.

In step S704, base plate 61 is coupled to disk spindle assemblycartridge 40. For example, a bore in pivot arm 77 on base plate 61 maybe aligned with pivot pin 47 on disk spindle assembly cartridge 40,thereby pivotally coupling base plate 61 to disk spindle assemblycartridge 40. Base plate 61 may be pivoted about pivot pin 47 untilalignment mount 78 meets and aligns with alignment mount 48 on diskspindle assembly cartridge 40. Base plate 61 may be secured to diskspindle assembly cartridge 40 using thumb screw 79 threaded throughalignment mount 78 and alignment mount 48.

In step S705, base plate 61 is attached to tester chassis 20. Base plate61 may be attached to tester chassis 20 using one or more clamps 24 orother fasteners. In step S706, the flex cable assembly of head stackassembly 64 is electrically connected to printed circuit board assembly80 mounted on tester chassis 20. As described above, the flex cableassembly of head stack assembly 64 may be brought into electricallycontact with an interface on printed circuit board assembly 80. Thiselectrical contact may be facilitated by raising printed circuit boardassembly 80 mounted on mount 25 by operation of clamp 29 and slideassemblies 28.

As described above, tester 10 is a modular hard drive component tester.Tester 10 is designed to allow one or more of the modules making up thesystem to be exchanged relatively quickly and easily. For example,tester 10 may be used to test head stack assemblies. To test a series ofhead stack assemblies, tester 10 may be arranged as shown in FIG. 6,with disk pack assembly cartridge 40 and printed circuit board assembly80 mounted to tester chassis 20. Each of the head stack assemblies maybe mounted in respective head stack assembly cartridges 60, which aresequentially mounted on tester chassis 20. Once mated with disk spindleassembly cartridge 40 and electrically connected to an interface onprinted circuit board assembly 80, the head stack assembly may betested. Once testing is complete, the head stack assembly cartridge isremoved from tester chassis 20 and the next head stack assemblycartridge is mounted. Alternatively, cover plate 65 may be removed frombase plate 61 while head stack assembly cartridge 60 remains mounted totester chassis 20. Once cover plate 65 is removed, an operator can swaphead stack assembly 64 or a head gimbal assembly detachably mounted tothe actuator arm of head stack assembly 64 and replace cover plate 65.Similar processes may be used to exchange magnetic disks in disk spindleassembly cartridges either by swapping the disk spindle assemblycartridge mounted on the tester chassis or by removing cover plate 45.

The hard drive component tester described herein is not limited to themounting and alignment configurations described above. For example,tester chassis 20 may be configured with tracks in which disk spindleassembly cartridge 40 and head stack assembly cartridge 60 are slidablymounted using rails or another structure corresponding to the tracks ontester chassis 20. The tracks on tester chassis 20 and the rails on diskspindle assembly cartridge 40 and head stack assembly cartridge 60 keepthe components aligned with one another when mounted on tester chassis20. Clamps or other locking mechanisms may be used to hold disk spindleassembly cartridge 40 and head stack assembly cartridge 60 together andin place during test operations.

The previous description is provided to enable any person skilled in theart to practice the various aspects described herein. Variousmodifications to these aspects will be readily apparent to those skilledin the art, and the generic principles defined herein may be applied toother aspects. Thus, the claims are not intended to be limited to theaspects shown herein, but is to be accorded the full scope consistentwith the language claims, wherein reference to an element in thesingular is not intended to mean “one and only one” unless specificallyso stated, but rather “one or more.” Unless specifically statedotherwise, the term “some” refers to one or more. Pronouns in themasculine (e.g., his) include the feminine and neuter gender (e.g., herand its) and vice versa. Headings and subheadings, if any, are used forconvenience only and do not limit the invention.

A phrase such as an “aspect” does not imply that such aspect isessential to the subject technology or that such aspect applies to allconfigurations of the subject technology. A disclosure relating to anaspect may apply to all configurations, or one or more configurations. Aphrase such as an aspect may refer to one or more aspects and viceversa. A phrase such as a “configuration” does not imply that suchconfiguration is essential to the subject technology or that suchconfiguration applies to all configurations of the subject technology. Adisclosure relating to a configuration may apply to all configurations,or one or more configurations. A phrase such a configuration may referto one or more configurations and vice versa.

The word “exemplary” is used herein to mean “serving as an example orillustration.” Any aspect or design described herein as “exemplary” isnot necessarily to be construed as preferred or advantageous over otheraspects or designs.

All structural and functional equivalents to the elements of the variousaspects described throughout this disclosure that are known or latercome to be known to those of ordinary skill in the art are expresslyincorporated herein by reference and are intended to be encompassed bythe claims. Moreover, nothing disclosed herein is intended to bededicated to the public regardless of whether such disclosure isexplicitly recited in the claims. No claim element is to be construedunder the provisions of 35 U.S.C. §112, sixth paragraph, unless theelement is expressly recited using the phrase “means for” or, in thecase of a method claim, the element is recited using the phrase “stepfor.” Furthermore, to the extent that the term “include,” “have,” or thelike is used in the description or the claims, such term is intended tobe inclusive in a manner similar to the term “comprise” as “comprise” isinterpreted when employed as a transitional word in a claim.

1. A head stack assembly cartridge, comprising: a base plate having apivot shaft for pivotally mounting a head stack assembly; a base voicecoil motor magnet attached to an inner surface of the base plate,wherein the base voice coil motor magnet is arranged on the innersurface of the base plate to be adjacent to a coil of the head stackassembly pivotally mounted on the pivot shaft: a cover removablyattached to the base plate; and a pivot clamp removably attached to thecover and configured to secure the head stack assembly pivotally mountedon the pivot shaft, wherein the pivot clamp is configured to be seatedon a fulcrum on the cover and on a pivot screw attaching the head stackassembly to the pivot shaft of the base plate, and wherein the pivotclamp is removably attached to the cover with a load screw operable toapply a load to the pivot screw.
 2. The head stack assembly cartridgeaccording to claim 1, wherein the pivot clamp comprises a triangularplate having a first corner and a second corner configured to be seatedon the fulcrum and a third corner configured to be seated on the pivotscrew.
 3. The head stack assembly cartridge according to claim 2,wherein the fulcrum comprises a first pin and a second pin set in thecover, the first pin arranged to seat the first corner of the pivotclamp and the second pin arranged to seat the second corner of the pivotclamp.
 4. The head stack assembly cartridge according to claim 3, thepivot clamp further comprising a third pin set in the third corner ofthe pivot clamp and arranged to be seated on the pivot screw.
 5. Thehead stack assembly cartridge according to claim 4, wherein the loadscrew for removably attaching the pivot clamp to the cover is arrangedalong an altitude of the triangular plate extending from the thirdcorner.
 6. A head stack assembly cartridge, comprising: a base platehaving a pivot shaft for pivotally mounting a head stack assembly; abase voice coil motor magnet attached to an inner surface of the baseplate, wherein the base voice coil motor magnet is arranged on the innersurface of the base plate to be adjacent to a coil of the head stackassembly pivotally mounted on the pivot shaft; a cover removablyattached to the base plate; and a pivot clamp removably attached to thecover and configured to secure the head stack assembly pivotally mountedon the pivot shaft, wherein the base plate further comprises a pivot armconfigured to pivotally couple the head stack assembly cartridge to adisk spindle assembly pack.
 7. The head stack assembly cartridgeaccording to claim 6, wherein the pivot arm comprises a bore arranged toreceive a pivot pin of the disk spindle assembly pack.
 8. The head stackassembly cartridge according to claim 6, wherein the base plate furthercomprises an alignment mount configured to align the head stack assemblycartridge with the disk spindle assembly pack in a closed position. 9.The head stack assembly cartridge according to claim 8, wherein thealignment mount further comprises a fastener for securing the head stackassembly cartridge to the disk spindle assembly pack.
 10. The head stackassembly cartridge according to claim 9, wherein the fastener comprisesa thumb screw.
 11. The head stack assembly cartridge according to claim6, further comprising a ramp attached to the inner surface of the baseplate, wherein the ramp is configured to support a head gimbal assemblyof the head stack assembly in a parked position.
 12. The head stackassembly cartridge according to claim 6, further comprising: a firststop attached to the inner surface of the base plate and arranged tolimit the angular displacement of the head stack assembly in a firstdirection; and a second stop attached to the inner surface of the baseplate and arranged to limit the angular displacement of the head stackassembly in a second direction.
 13. The head stack assembly cartridgeaccording to claim 6, further comprising a cover voice coil motor magnetattached to an inner surface of the cover, wherein the cover voice coilmotor magnet is arranged on the inner surface of the cover opposite thebase voice coil motor magnet attached to the inner surface of the baseplate and to be adjacent to the coil of the head stack assemblypivotally mounted on the pivot shaft.